Ester-containing compositions

ABSTRACT

Ester-containing compositions prepared by reacting a high molecular weight carboxylic acid acylating agent with polyoxyalkylene alcohol demulsifiers for aqueous emulsions. The ester-containing compositions are useful as additives in normally liquid fuels and lubricants.

This application is a continuation-in-part of my application Ser. No.152,425 filed June 11, 1971, now abandoned, which was a divisionalapplication of my application Ser. No. 12,838 filed Feb. 19, 1970, nowabandoned. Ser. No. 12,838 was a continuation-in-part of my earlierfiled application Ser. No. 823,990 filed May 12, 1969, now abandoned.

This invention relates to novel compositions of matter, processes fortheir preparation, and to lubricants and fuels containing these novelcompositions. Particularly, this invention is broadly concerned withcompositions produced by reacting certain carboxylic acid acylatingagents with (1) polyoxyalkylene alcohols, or (2) polyoxyalkylenealcohols and one or more polyhydric alcohols, amines, or basicallyreacting alkaline earth metal compounds.

It is now well-known that esters and acylated amines prepared byreacting high molecular weight mono- or polycarboxylic acids withalcohols and amines are useful as additives in lubricants and fuelswhere they function as dispersants or detergents and otherwise promoteengine cleanliness. The state of the art with respect to these additivesis represented by U.S. Pat. No. 3,163,603 (reissued as 26,433);3,172,892; 3,184,474; 3,219,666; 3,272,746; 3,307,928; 3,331,776;3,341,542; 3,346,354; and 3,381,022.

While these materials have achieved widespread commercial acceptance asadditives for lubricants and fuels, their use has not been entirelywithout some problems and there is a continuing effort to improve theirperformance. For example, it is reported in U.S. Pat. No. 3,347,645 thatacylated nitrogen compositions prepared by reacting alkenyl-substitutedsuccinic anhydrides with polyamines function effectively as dispersantsin gasoline but promote aqueous emulsion in the gasoline during storageand shipment. Furthermore, the presence of these new dispersantssometimes promotes the formation of an aqueous emulsions on internalengine surfaces where water vapors can condense in the presence of oilsuch as on rocker arm covers and oil-fill caps. The use of these newdispersants in lubricants has sometimes been accompanied by rustproblems.

According to the present invention, there is provided a novel class ofdispersants having improved characteristics with regard to varnishreduction, dispersancy, as well as the aqueous emulsion and rustproblems. These novel compositions can be used as lubricant and fueladditives in the same manner as the prior art dispersants disclosed inthe above-listed U.S. patents.

In accordance with the foregoing, it is a principal object of thisinvention to provide novel compositions of matter. Another object is toprovide novel compositions of matter useful as additives in lubricantsand fuels. A further object is to provide novel compositions of matteruseful as detergents and dispersants in lubricants and fuels. A stillfurther object is to provide lubricants and fuels containing asdetergent and dispersant additives the novel compositions of thisinvention. An additional object is to provide processes for preparingthese novel compositions.

These as well as other objects of this invention can be achieved byproviding a process for preparing ester-containing compositionscomprising the steps of reacting under esterification conditions (A) atleast one carboxylic acid acylating agent having an average of at leastthirty aliphatic carbon atoms per molecule exclusive of carboxyl carbonatoms with (B) at least one polyoxyalkylene alcohol demulsifier foraqueous emulsions, the total amount of (A) and (B) used in the reactionbeing such that there is about 0.001 equivalent of (B) for eachequivalent (A). Another aspect of the invention can be achieved by theadditional step of contacting (C) at least one member selected from thegroup consisting of polyhydric alcohols, amines, and basically reactingalkaline earth metal compounds with the ester-containing composition,the total amount of (C) being such that there is at least about 0.01equivalent of (C) for each equivalent of (A). A further embodiment ofthe invention can be achieved by providing a process wherein (A) isreacted with (B) and at least one member selected from the groupconsisting of (C) polyhydric alcohols, amines, and basically reactingalkaline earth metal compounds, the total amount of (C) being such thatthere is at least 0.01 equivalent of (C) for each equivalent of (A). Thenovel compositions contemplated by the present invention are thoseproduced in accordance with these processes while lubricants and fuelscontemplated are readily achieved by incorporating these compositionsinto lubricating oils, greases, or other lubricants or into a normallyliquid fuel such as a petroleum distillate fuel, e.g., kerosene, dieselfuel, fuel oil, gasolines, jet aviation fuel, and the like.

The carboxylic acid acylating agents, (A) above, is the carboxylic acidper se or an acylating agent derived from a mono- or polycarboxylicacid. An important characteristic of the acylating agent is its size. Itshould contain at least thirty, preferably at least about fifty,aliphatic carbon atoms exclusive of the carboxyl carbon atoms. Thislimitation is based upon both oil-solubility considerations and theeffectiveness of the compositions as additives in lubricants and fuels.Another important aspect of the acylating agent is that it preferablyshould be substantially saturated, i.e., at least about 95% of the totalnumber of the carbon-to-carbon covalent linkages therein preferablyshould be saturated linkages. In an especially preferred aspect of theinvention, at least about 98% of these covalent linkages are saturated.Obviously, all of the covalent linkages may be saturated. A greaterdegree of unsaturation renders the esters more susceptible to oxidation,degradation, and polymerization and this lessens the effectiveness ofthe final products as lubricant and fuel additives. In addition, theacylating agent should be substantially free from oil-solubilizingpendant groups, that is, groups having more than about six aliphaticcarbon atoms. Although, some such oil-solubilizing pendant groups may bepresent, they preferably will not exceed one such group for everytwenty-five aliphatic carbon atoms in the principal hydrocarbon chain.

The acylating agent may contain polar substituents provided that thepolar substituents are not present in proportions sufficiently large toalter significantly the hydrocarbon character of the radical. Typicalsuitable polar substituents are halo, such as chloro and bromo, oxo,oxy, formyl, sulfonyl, sulfinyl, thio, nitro, etc. Such polarsubstituents, if present, preferably will not exceed 10% by weight ofthe total weight of the hydrocarbon portion of the carboxylic acidradical exclusive of the carboxyl group. The carboxylic acid acylatingagents also may contain cyclic and/or aromatic groups. However, theyshould be essentially aliphatic in nature. The preferred acylatingagents are aliphatic mono- and polycarboxylic acids, anhydrides, ormixtures thereof.

Carboxylic acid acylating agents suitable for preparing the esters arewell-known in the art and have been described in detail, for example, inU.S. Pat. Nos. 3,087,936; 3,163,603; 3,172,892; 3,189,544; 3,215,707;3,219,666; 3,231,587; 3,272,746; 3,288,714; 3,306,907; 3,331,776;3,340,281; 3,341,542; 3,346,354; and 3,381,022. In the interest ofbrevity, these patents are incorporated herein for their disclosure ofsuitable mono- and polycarboxylic acid acylating agents which can beused for the preparation of the esters used as starting materials in thepresent invention.

As disclosed in the foregoing patents, there are several processes forpreparing the acids. Generally, the process involves the reaction of (1)an ethlenically unsaturated carboxylic acid, lower alkyl ester, acidhalide, or anhydride with (2) an ethylenically unsaturated polyolefincontaining at least about thirty aliphatic carbon atoms or a halogenatedpolyolefin or hydrocarbon containing at least about thirty aliphaticcarbon atoms at a temperature within the range of about 100° -300°C. Thehalogenated hydrocarbon, usually a brominated or chlorinated hydrocarbonas well as an ethylenically unsaturated hydrocarbon reactant can, ofcourse, containing polar substituents, oil-solubilizing pendant groupsand be unsaturated within the general limitations explained hereinabove.It is these hydrocarbon reactants which provides most of the aliphaticcarbon atoms present in the acyl moiety of the acylating agent.

When preparing the carboxylic acid acylating agent according to thesetwo processes, the carboxylic acid reactant usually corresponds to theformula R_(o) -(COOH)_(n), where R_(o) is characterized by the presenceof at least one ethylenically unsaturated carbon-to-carbon covalent bondand n is an integer from one to six and preferably one or two. The acidreactant can also be the corresponding carboxylic acid halide,anhydride, ester, or other equivalent acylating derivative and mixturesof one or more of these. Ordinarily, the total number of carbon atoms inthe acid reactant will not exceed ten and generally will not exceed six.Preferably the acid reactant will have at least one ethylenic linkage inan α,β-position with respect to at least one carboxyl function.Exemplary acidic reactants are acrylic acid, methacrylic acid, maleicacid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride,citraconic acid, citraconic anhydride, mesaconic acid, glutaconic acid,chloromaleic acid, aconitic acid, crotonic acid, methylcrotonic acid,sorbic acid, 3-hexenoic acid, 10-decenoic acid,2-pentene-1,3,5-tricarboxylic acid, and the like. Due to considerationsof economy and availability, these acid reactants usually employed areacrylic acid, methacrylic acid, maleic acid, and maleic anhydride.

The substantially saturated aliphatic hydrocarbon-substituted succinicacid and anhydrides are especially preferred as acylating agents. Thesesuccinic acid acylating agents are readily prepared by reacting maleicanhydride with a high molecular weight olefin or a halogenatedhydrocarbon such as a chlorinated polyolefin. The reaction involvesmerely heating the two reactants at a temperature of about 100° -300°C.,preferably, 100° -200°C. The product from such a reaction is asubstituted succinic anhydride where the substituent is derived from theolefin or chlorinated hydrocarbon as described in the above citedpatents. The product may be hydrogenated to remove all or a portion ofany ethylenically unsaturated covalent linkages by standardhydrogenation procedures, if desired. The substituted succinicanhydrides may be hydrolyzed by treatment with water or steam to thecorresponding acid and either the anhydride or the acid may be convertedto the corresponding acid halide or ester by reacting with phosphorushalide, phenols, or alcohols.

The acylating agents can also be prepared by contacting a polyolefinwith an acid of the formula R_(o) -(COOH)_(n) in the presence ofchlorine according to the techniques disclosed in U.S. Pat. Nos.3,215,707 and 3,231,587.

The acylating agents may also be prepared by halogenating a highmolecular weight hydrocarbon such as the above described olefin polymersto produce a poly-halogenated product, converting the poly-halogenatedproduct to a poly-nitrile, and then hydrolyzing the poly-nitrile. Theymay be prepared by oxidation of a high molecular weight polyhydricalcohol with potassium permanganate, nitric acid, or a similar oxidizingagent. Mono-carboxylic acid acylating agents may be obtained byoxidizing a mono-alcohol with potassium permanganate or by reacting ahalogenated high molecular weight olefin polymer with a ketene. Anotherconvenient method for preparing monocarboxylic acid involves thereaction of metallic sodium with an acetoacetic ester or a malonic esterof an alkanol to form a sodium derivative of the ester and thesubsequent reaction of the sodium derivative with a halogenated highmolecular weight hydrocarbon such as brominated wax or brominatedpolyisobutene.

Mono-carboxylic and poly-carboxylic acid acylating agents can also beobtained by reacting chlorinated mono- and poly-carboxylic acids,anhydrides, acyl halides, and the like with ethylenically unsaturatedhydrocarbons or ethylenically unsaturated substituted hydrocarbons suchas the polyolefins and substituted polyolefins described hereinbefore inthe manner described in U.S. Pat. No. 3,340,281.

The mono-carboxylic and poly-carboxylic acid anhydrides are obtained bydehydrating the corresponding acids. Dehydration is readily accomplishedby heating the acid to a temperature above about 70°C., preferably inthe presence of a dehydration agent, e.g. acetic anhydride. Cyclicanhydrides are usually obtained from poly-carboxylic acids having acidradicals separated by no more than three carbon atoms such assubstituted succinic or glutaric acid, whereas linear anhydrides areobtained from poly-carboxylic acids having the acid radicals separatedby four or more carbon atoms. The acid halides of the mono-carboxylicand poly-carboxylic acids can be prepared by the reaction of the acidsor their anhydrides with a halogenating agent such as phosphorustribromide, phosphorus pentachloride, or thionyl chloride.

The ethylenically unsaturated hydrocarbon reactant and the halogenatedhydrocarbon reactant used in the preparation of the acylating agents areprincipally the high molecular weight, substantially saturated petroleumfractions and substantially saturated olefin polymers and thecorresponding chlorinated products. The 1-olefin polymers andchlorinated 1-olefin polymers derived from mono-olefins having from twoto about thirty carbon atoms are preferred. The especially usefulpolymers are the polymers of 1-monoolefins such as ethylene, propene,1-butene, isobutene, 1-hexene, 1-octene, 2-methyl-1-heptene,3-cyclohexyl-1-butene, and 2-methyl-5-propyl-1-hexene. Polymers ofmedial olefins, i.e., olefins in which the olefinic linkage is not atthe terminal position, likewise are useful. These are exemplified by2-butene, 3-pentene, and 4-octene.

The interpolymers of 1-monoolefins such as illustrated above with eachother and with other interpolymerizable olefinic substances such asaromatic olefins, cyclic olefins, and polyolefins, are also usefulsources of the ethylenically unsaturated reactant. Such interpolymersinclude for example, those prepared by polymerizing ethylene withpropylene, isobutene with styrene, isobutene with butadiene, propenewith isoprene, propene with isobutene, ethylene with piperylene,isobutene with chloroprene, isobutene with p-methyl-styrene, 1-hexenewith 1,3-hexadiene, 1-octene with 1-hexene, 1-heptene with 1-pentene,3-methyl-1-butene with 1-octene, 3,3-dimethyl-1-pentene with 1-hexene,isobutene with styrene and piperylene, etc.

The halogenated hydrocarbons, halogenated polyolefins, and ethylenicallyunsaturated hydrocarbons used in the preparation of the acylating agentscan have molecular weights of from about 700 up to about 100,000 or evenhigher. The preferred polyolefins and halogenated polyolefins are thosehaving an average molecular weight of about 700 to about 5,000.

In lieu of the high molecular weight hydrocarbons and halogenatedhydrocarbons discussed above, hydrocarbons containing activating polarsubstituents which are capable of activating the hydrocarbon molecule inrespect to reaction with an ethylenically unsaturated acid reactant maybe used in the above-illustrated reactions for preparing the acylatingagents. Such polar substituents include sulfide and disulfide linkages,and nitro, mercapto, carbonyl, and formyl radicals. Examples of thesepolar-substituted hydrocarbons include polypropene sulfide,dipolyisobutene disulfide, nitrated mineral oil, di-polyethylenesulfide, etc.

Reactant (B) is a polyoxyalkylene alcohol which is a demulsifier foraqueous emulsions. The terminology "demulsifier for aqueous emulsions"as used in the present specification and claims is intended to describethose polyoxyalkylene alcohols which are capable of preventing orretarding the formation of aqueous emulsions or "breaking" aqueousemulsions. The terminology "aqueous emulsion" is generic tooil-in-water, water-in-oil, fuel-in-water, and water-in-fuel-emulsions.

Many commercially available polyoxyalkylene alcohol demulsifiers can beused as reactant (B). Useful demulsifiers are the reaction products ofvarious organic amines, carboxylic acid amides, and quaternary ammoniumsalts with ethyleneoxide. Such polyoxyethylated amines, amides, andquaternary salts are available from Armour Industrial Chemical Co. underthe names ETHODUOMEEN T, an ethyleneoxide condensation product of anN-alkyl alkylenediamine under the name DUOMEEN T; ETHOMEENS, tertiaryamines which are ethyleneoxide condensation products of primary fattyamines; ETHOMIDS, ethyleneoxide condensates of fatty acid amides; andETHOQUADS, polyoxyethylated quaternary ammonium salts such as quaternaryammonium chlorides.

The preferred demulsifiers are liquid polyoxyalkylene alcohols andderivatives thereof. The derivatives contemplated are the hydrocarbylethers and the carboxylic acid esters obtained by reacting the alcoholswith various carboxylic acids. Illustrative hydrocarbyl groups arealkyl, cycloalkyl, alkylaryl, aralkyl, alkylaryl alkyl, etc., containingup to about forty carbon atoms. Specific hydrocarbyl groups are methyl,butyl, dodecyl, tolyl, phenyl, naphthyl, dodecylphenyl, p-octylphenylethyl, cyclohexyl, and the like. Carboxylic acids useful in preparingthe ester derivatives are mono- or polycarboxylic acids such as aceticacid, valeric acid, lauric acid, acid, succinic acid, and alkyl oralkenyl-substituted succinic acids wherein the alkyl or alkenyl groupcontains up to about twenty carbon atoms. Members of this class ofalcohols are commercially available from various sources; e.g., PLURONICpolyols from Wyandotte Chemicals Corporation; POLYGLYCOL 112--2, aliquid triol derived from ethyleneoxide and propyleneoxide availablefrom Dow Chemical Co.; and TERGITOLS, dedecylphenyl or nonylphenylpolyethylene glycol ethers, and UCONS, polyalkylene glycols and variousderivatives thereof, both available from Union Carbide Corporation.However, the demulsifiers used as reactant (B) must have an average ofat least one free alcoholic hydroxyl group per molecule ofpolyoxyalkylene alcohol. An alcoholic hydroxyl group is one attached toa carbon atom that does not form part of an aromatic nucleus.

In this class of preferred polyoxyalkylene alcohols are those polyolsprepared as "block" polymers. Thus, a hydroxy-substituted compound,R--(OH)m (where m is 1 to 6, preferably 2 to 3, and R is the residue ofa mono- or polyhydric alcohol or mono- or polyhydroxy phenol, naphthol,etc.) is reacted with an alkylene oxide, ##EQU1## to form a hydrophobicbase, R' being a lower alkyl group of up to four carbon atoms, R" beingH or the same as R' with the proviso that the alkylene oxide does notcontain in excess of ten carbon atoms. This base is then reacted withethylene oxide to provide a hydrophylic portion resulting in a moleculehaving both hydrophobic and hydrophylic portions. The relative sizes ofthese portions can be adjusted by regulating the ratio of reactants,time of reaction, etc., as is obvious to those skilled in the art. It iswithin the skill of the art to prepare such polyols whose molecules arecharacterized by hydrophobic and hydrophylic moieties present in a ratiorendering them suitable as demulsifiers for aqueous emulsions in variouslubricant and fuel compositions and thus suitable as reactant (B). Thus,if more oil- or fuel-solubility is needed in a given lubricant or fuelcomposition, the hydrophobic portion can be increased and/or hydrophylicportion decreased. If greater aqueous emulsion breaking capability isrequired, the hydrophylic and/or hydrophobic portions can be adjusted toaccomplish this.

Compounds illustrative of R--(OH)m include aliphatic polyols such as thealkylene glycols and alkane polyols, e.g., ethylene glycol, propyleneglycol, trimethylene glycol, glycerol, pentaerythritol, erythritol,sorbitol, mannitol, and the like and aromatic hydroxy compounds such asalkylated mono- and polyhydric phenols and naphthols e.g., cresols,heptylphenols, dodecylphenols, dioctylphenols, triheptylphenols,resorcinol, pyrogallol, etc.

Polyoxyalkylene polyol demulsifiers which have two to three hydroxylgroups and molecules consisting essentially of hydrophobic portionscomprising ##EQU2## groups where R' is lower alkyl of up to three carbonatoms and hydrophylic portions comprising --CH₂ CH₂ O-- groups areparticularly preferred as reactant (B). Such polyols can be prepared byfirst reacting a compound of the formula R-- (OH)m where m is 2-3 with aterminal alkylene oxide of the formula ##EQU3## and then reacting thatproduct with ethylene oxide. R--(OH)m can be, for example, TMP(trimethylolpropane), TME (trimethylolethane), ethylene glycol,trimethylene glycol, tetramethylene glycol, tri-(β-hydroxypropyl)-amine,1,4-(2-hydroxyethyl)-cyclohexane, N,N,N' ,N'-tetrakis(2-hydroxypropyl)ethylene diamine, N,N,N',N'-tetrakis(2-hydroxyethyl)-ethylene diamine, naphthol, alkylated naphthol,resorcinol, or one of the other illustrative examples mentionedhereinbefore.

The polyoxyalkylene alcohol demulsifiers should have an averagemolecular weight of about 1000 to about 10,000, preferably about 2000 toabout 7000. The ethyleneoxy groups (i.e., --CH₂ CH₂ O--) normally willcomprise from about 5% to about 40% of the total average molecularweight. Those polyoxyalkylene polyols where the ethyleneoxy groupscomprise from about 10% to about 30% of the total average molecularweight are especially useful as reactant (B). Polyoxyalkylene polyolshaving an average molecular weight of about 2500 to about 6000 whereapproximately 10% -20% by weight of the molecule is attributableethyleneoxy groups result in the formation of esters having particularlyimproved properties. The ester and ether derivatives of these polyolsare also useful as reactant (B).

Representative of such polyoxyalkylene polyols are the liquid polyolsavailable from Wyandotte Chemicals Company under the name PLURONICPolyols and other similar polyols. These PLURONIC Polyols correspond tothe Formula I: ##EQU4## wherein x, y, and z integers greater than 1 suchthat the CH₂ CH₂ O groups comprise from about 10% to about 15% by weightof the total molecular weight of the glycol, the average molecule weightof said polyols being from about 2500 to about 4500. This type of polyolcan be prepared by reacting propylene glycol with propylene oxide andthen with ethylene oxide.

Another group of polyoxyalkylene alcohol demulsifiers illustrative ofthe preferred class discussed above are the commercially availableliquid TETRONIC polymers sold by Wyandotte Chemicals Corporation. Thesepolyols are represented by the general formula: ##EQU5## Such polyolsare described in U.S. Pat. No. 2,979,528 which is expressly incorporatedherein by reference. Those polyols corresponding to the above formulahaving an average molecular weight of up to about 10,000 wherein theethyleneoxy groups contribute to the total molecular weight in thepercentage ranges discussed above are preferred. A specific examplewould be such a polyol having an average molecular weight of about 8000wherein the ethyleneoxy groups account for 7.5% -12% by weight of thetotal molecular weight. Such polyols can be prepared by reacting analkylene diamine such as ethylene diamine, propylene diamine,hexamethylene diamine, etc., with propylene oxide until the desiredweight of the hydrophobic portion is reached. Then the resulting productis reacted with ethylene oxide to add the desired number of hydrophylicunits to the molecules.

Another commercially available polyoxyalkylene polyol falling withinthis preferred group is Dow polyglycol 112--2, a triol having an averagemolecular weight of about 4000-5000 prepared from propylene oxides andethylene oxides, the ethyleneoxy groups comprising about 18% by weightof the triol. Such triols can be prepared by first reacting glycerol,TME, TMP, etc,, with propylene oxide to form a hydrophobic base andreacting that base with ethylene oxide to add hydrophylic portions.

Reactant (C) is at least one member selected from the class consistingof polyhydric alcohols, amines, and basically reacting Group II a metalcompounds. Thus (C) can be a single polyhydric alcohol, a mixture ofpolyhydric alcohols, a combination of a single polyhydric alcohol and asingle basically reacting metal compound, a single amine or a mixture ofvarious amines, a combination of a mixture of polyhydric alcohols and amixture of ethylene polyamines, a combination of a single type of amineand a single basically reacting metal compound, a mixture of variousGroup II a basically reacting metal compounds and the like. Preferablyreactant (C) is a polyhydric alcohol.

The polyhydric alcohols useful as reactant (C) generally have from twoto ten hydroxyl groups and up to twenty aliphatic carbon atoms. They arequite diverse in structure and chemical composition. Typical polyhydricalcohols are alkylene glycols such as ethylene glycol, propylene glycol,trimethylene glycol, butylene glycol, and polyglycols such as diethyleneglycol, triethylene glycol, tetraethylene glycol, dipropylene glycol,tripropylene glycol, dibutylene glycol, tributylene glycol, and otheralkylene glycols and polyalkylene glycols in which the alkylene radicalcontains from 2 to about 8 carbon atoms. Other useful polyhydricalcohols include glycerol, monomethyl ether of glycerol,pentaerythritol, 9,10 -dihydroxystearic acid, the ethyl ester of9,10-dihydroxystearic acid, 3-chloro-1,2-propanediol, 1,2-butanediol,1,4-butanediol, 2,3-hexanediol, 2,3-hexanediol, pinacol, erythritol,arabitol, sorbitol, mannitol, 1,2-cyclohexanediol, 1,4-cyclohexanediol,1,4-(2-hydroxyethyl)-cyclohexane, 1,4-dihydroxy-2-nitro-butane,1,4-di(2-hydroxyethyl)-benzene, dipentaerythritol, copolymers of allylalcohol and styrene, the carbonhydrates such as glucose, arabitose,ramnose, mannose, and galactose, amino alcohols such asdi(2-hydroxyethyl)amine, tri-(3-hydroxypropyl)amine,N,N'-di(hydroxyethyl)ethylenediamine, N,N-di-(2-hydroxylethyl) glycineand esters thereof with lower mono- and polyhydric aliphatic alcohols,N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine,N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine; and the like.

Included within this group of polyhydric alcohols are those charcterizedby the presence of at least two free hydroxyl groups and at least onehydroxyl group which has been esterified with a mono-carboxylic acidhaving from eight to about thirty carbon atoms such as octanoic acid,oleic acid, stearic acid, linoleic acid, dodecanoic acid, or tall oilacid. Examples of such partially esterified polyhydric alcohols are themono-oleate of sorbitol, the mono-oleate of glycerol, the mono-stearateof glycerol, the di-stearate of sorbitol, and the di-dodecanoate oferythritol.

A preferred class of alcohols are the polyhydric aliphatic alcoholscontaining up to ten carbon atoms. This class of alcohols includesglycerol, erythritol, pentaerythritol, glyconic acid, glyceraldehyde,glucose, arabinose, 1,7-heptanediol, 2,4-heptanediol, 1,2,3-hexanetriol,1,2,4-hexanetriol, 1,2,5-hexanetriol, 2,3,4-hexanetriol,1,2,3-butanetriol, 1,2,4-butanetriol, quinic acid,2,2,6,6-tetrakis-(hydroxymethyl)-cyclohexanol, 1,10-decanediol,digitalose, and the like. The polyhydric aliphatic alcohols containingat least three hydroxyl groups and up to ten carbon atoms areparticularly preferred.

An especially preferred class of polyhydric alcohols are the polyhydricalkanols containing three to ten, especially three to six carbon atomsand having at least three hydroxyl groups. Such alcohols are exemplifiedby glycerol, β-hydroxymethyl-2-methyl-1,3-propanediol (i.e.,trimethylolethane or TME), 2-hydroxymethyl-2-ethyl-1,3-propanediol(i.e., trimethylolpropane or TMP), 1,2,4-butanetriol, 1,2,6-hexanetriol,1,2,3-pentanetriol, 1,2,3-hexanetriol, 1,2,4-hexanetriol,1,2,5-hexanetriol, 2,3,4-hexanetriol, mannitol, pentaerythritol,sorbitol, and mixtures thereof. The most preferred polyhydric alkanolsare those containing at least four hydroxy groups. This class isexemplified by pentaerythritol, erythritol, threitol, ribitol, xylitol,arabitol, sorbitol, mannitol, and mixtures of two or more of thesealcohols.

The amines contemplated as being useful as reactant (C) are primary orsecondary amines characterized by a radical having the configuration##EQU6## The two remaining valences of the nitrogen atom of the ##EQU7##radical preferably are satisfied by hydrogen, amino, substituted amino,or an organic radical bonded to said nitrogen atom through directcarbon-to-nitrogen linkages. These amines include ammonia, aliphaticmonoamines and polyamines, aromatic amines, heterocyclic amines,carboxylic amines, arylene amines, alkylene amines,N-hydroxyalkyl-substituted amines, and the like. Specific amines aremethylamine, N-methylethylamine, N-cyclohexyl-aniline, dibutylamine,cyclohexylamine, aniline, di(p-methylphenyl)amine, dodecylamine,octadecylamine, o-phenylenediamine,N,N'-di-(n-butyl)-p-phenylenediamine, morpholine, piperazine,pyrollidine, indole, piperidine, hexahydro-1,3,5-triazine,1-H-1,2,4-triazole, melamine, bis(p-aminophenyl)methane,phenylmethylamine, cyclohexylamine, pyrrolidine,3-amino-5,6-diphenyl-1,2,4-triazine, 2-octadecylimidazoline,2-phenyl-4-methyl-imidazolidine, oxazolidine, ethanolamine,diethanolamine, 2-heptyl-oxazolidine, N-(2-hydroxyethyl)ethylenediamine,N,N'-bis(2-hydroxyethyl)ethylenediamine, 1-(2-hydroxyethyl)piperazine,mono-hydroxypropyl-substituted diethylenetriamine,1-(2-hydroxypropyl)piperazine, di-(hydroxypropyl)-substitutedtetraethylenepentamine, N-(3-hydroxypropyl)tetramethylenediamine,N-(aminoalkyl)amines such as tris(aminoethyl)amine, and1-di(2-aminoethyl)-diethylenetriamine.

The preferred amines are the alkylenepolyamines conforming for the mostpart to the formula ##EQU8## where p is an integer of one to nine and R"is hydrogen, alkyl, hydroxyalkyl, aminoalkyl, or ##EQU9## where p' is aninteger of one to nine providing p and p' do not exceed nine, R'" ishydrogen, alkyl, hydroxylalkyl, aminoalkyl and at least one R" permolecule is hydrogen. The alkylene radicals can contain one to sevencarbon atoms. These alkylene polyamines include principallymethylenepolyamines, ethylenepolyamines, butylenepolyamines,propylenepolyamines, pentylenepolyamines, hexylenepolyamines,heptylenepolyamines, octylenepolyamines, other polymethylene amines, thecyclic analogs and the higher homologs of these amines such aspiperazine and aminoalkyl-substituted piperazines. Thehydroxyalkyl-substituted and aminoalkyl-substituted polyamines includethose in which the alkyl group is a lower alkyl group, i.e., one havingno more than seven carbon atoms. Mixtures of such alkylenepolyamines maybe used as reactant (C). Indeed, in view of the fact that mostcommercially available alkylenepolyamines are mixtures, such mixtureswill normally be employed when it is desired to use an alkylenepolyamineas (C). The most preferred amines are the alkylene polyamines of FormulaII where the R" variables are hydrogen, aminoalkyl, or ##EQU10## whereinR'" is hydrogen and the alkylene groups are ethylene or propylene andmixtures of such polyamines.

Another class of especially suitable amines can be described aspolyoxyalkylene polyamines. This class of amines can be genericallyrepresented by the formulae

    H.sub.2 N--alkylene--O-alkylene).sub.r NH.sub.2

or

    R[--O-alkylene).sub.s NH.sub.2 ].sub.3-6

where r has an average value of about 2 to about 40, s has an averagevalue of about 1 to about 12 with the proviso that each--O-alkylene)_(s) group on a given molecule may have a different valuefor s, R is a tri- to hexavalent organic radical, usually hydrocarbonradical and preferably a saturated aliphatic hydrocarbon radical such as##EQU11## and the alkylene groups may contain from two to eight carbonatoms but normally only two to four carbon atoms. Preferably, thealkylene groups are ethylene or propylene groups or mixtures of these.Such polyoxyalkylene polyamines are commercially available. For exampleJefferson Chemical Company, Inc., sells such polyamines under the namesJEFFAMINE D-230, D-400, D-1000, D-2000, and T-403.

Other suitable amines include ureas, thioureas, hydrazines, guanidines,amidines, amides, thioamides, cyanamides, etc. Specific examplesillustrating such compounds are: hydrazine, phenylhydrazine,N,N"-diphenylhydrazine, octadecylhydrazine, benzoylhydrazine, urea,thiourea, N-butylurea, stearylamide, oleylamide, guanidine,1,3-diphenylguanidine, 1,2,3-tributylguanidine, benzamidine,octadecamidine, N,N'-dimethylstearamidine, cyanamide, dicyandiamide,guanylurea, aminoguanidine, etc.

Reactant (C) can also be a group IIa basically reacting metal compound.Generally, the metal compound will be a lower alkoxide, an oxide, ahydroxide, a carbonate, a sulfide, a hydrosulfide, or amide. Specificexamples of these basically reacting metal compounds include bariumoxide, barium hydroxide, barium methoxide, calcium ethoxide, strontiumisopropoxide, calcium hydroxide, magnesium oxide, and the like. Thebasically reacting inorganic compounds of calcium, barium, and magnesiumare particularly preferred, especially the oxides and hydroxides,because of their availability, economy, and usefulness of the productsthereby obtained.

Reactant (D) is a base selected from the group consisting of amines,basically reacting Group IIa metal compounds, and mixtures of two ormore of these materials. The basically reacting metal compounds and theamines contemplated as being useful as reactant (D) are the same asthose described in the discussion of reactant (C) hereinabove. However,the amines are the preferred bases. The alkylene polyamines having fromtwo to three carbon atoms in the alkylene groups and from three to sevenamino nitrogens and mixtures thereof are especially useful. Thepolyoxyalkylene polyamines described hereinabove are also an especiallyuseful class of amines. Mixtures of alkylene polyamines andpolyoxyalkylene polyamines are also very useful as reactant (D).

The esterification conditions contemplated by the present invention arethose conditions conventionally employed in the preparation ofcarboxylic acid esters. Thus, the foregoing reactants are contacted andheated at a temperature of from about 50°C. up to the decompositiontemperature of that reactant having the lowest decomposition point, butgenerally at a temperature of at least 100°C. up to about 300°C.Reaction temperatures of about 150°C. to about 250°C. give good results.The duration of contact and heating of the various reactants willobviously depend on the identity of the particular reactant, thereaction temperature, the quantity of reactants, the presence ofcatalysts, and other well-known variables. For small quantities ofreactants contacted and heated on a laboratory scale, reaction time ofabout 0.1 to about twelve hours will generally be sufficient whilecommercial quantities of reactants contacted and heated in largecommercial reactors may require a greater period of heating, e.g., up totwenty-four hours or more.

The reactions involving the amine or basically reacting metal compoundsare obviously not esterification reactions. When the ester-containingcompositions are contacted with amines or when the acylating agents arereacted directly with the polyoxyalkylene alcohol demulsifier and anamine, unesterified carboxyl groups or equivalent acylating derivativesthereof ##EQU12## react with the amino groups to form amine salts,amides, imides, amidines, and mixturers of two or more of these.Similarly, the basically reacting metal compound reacts with unreactedcarboxyl groups to form metal carboxylate groups.

The esterification conditions include the use of conventionalesterification catalysts to promote the esterification reaction.Suitable catalyst include sulfuric acid, pyridine hydrochloride,hydrocloric acid, benzene sulfonic acid, p-toluene sulfonic acid,phosphoric acid, and other known esterification catalysts. The catalyst,if present, can be employed in amounts of from about 0.01% to about 5%by weight based on the total weight of acylating agent and alcoholpresent.

The reactants can be contacted in the presence or absence of liquiddiluents. Ordinarily, the presence of a diluent facilitates mixing,temperature control, and handling of the reaction mixture. Suitablediluent include the aliphatic, cycloaliphatic, and aromatic hydrocarbonsand the corresponding chlorinated hydrocarbons such as benzene, toluene,xylene, chlorobenzene, hexane, heptane, cyclohexane, or mixtures ofthese. Mineral oils are very good diluents, particularly if thecomposition produced by the reaction is one that is later to be employedin a mineral lubricating oil composition. Other inert organic diluentscan also be employed such as ethers, sulfoxides, sulfones, and the like.Where the reactant is itself a liquid at the reaction temperature, italso functions as a diluent and it is sometimes convenient to employ anexcess amount of a reactant to serve this purpose.

As the conditions ordinarily employed for preparing carboxylic acidesters of alcohols are well known, no further detailed description ofthese conventional esterification conditions is necessary. For example,a detailed discussion and illustration of esterification conditionssuitable for the process of the present invention is found in U.S. Pat.No. 3,481,022.

For purposes of describing the present invention, the number ofequivalents contained in a carboxylic acid acylating agent, (A) dependsupon the number of carboxyl groups present or equivalent acylatingfunctional derivatives thereof such as ##EQU13## and the like.Therefore, a polyisobutenyl-substituted succinic anhydride has twoequivalents per mole; a polypropylene-substituted acrylic acid has oneequivalent per mole; and a polyisobutylene containing an average of twosuccinic acid groups per molecule has four equivalents per mole. Thenumber of equivalents of alcohols, that is, reactant (B) or thepolyhydric alcohol reactants encompassed by (C) is determined by thenumber of hydroxyl groups present in the molecule. For example, apolyoxyalkylene alcohol demulsifier having one hydroxy group permolecule has one equivalent per average molecular weight thereof; apolyoxyalkylenediol demulsifier, two; a polyoxyalkylenetrioldemulsifier, three. Pentaerythritol, and erythritol each have fourequivalents per mole while glycerol, TME, and TMP each have threeequivalents per mole. The number of equivalents of an amine depends uponthe number of ##EQU14## groups present therein. Thus, an ethylenepolyamine having an average composition corresponding to that oftetraethylenepentamine has five equivalents per mole;diethylenetriamine, three; pentaethylenehexamine, six;1-(aminoalkyl)-piperazine, two. Obviously, Group IIa basically reactingmetal compounds contain two equivalents per mole. Thus, bariumhydroxide, barium oxide, barium ethoxide, and the like each contain twoequivalents per mole. Where a mixture of different reactants is used for(A), (B), (C), or (D), the number of equivalents contained in a givenamount of reactant will depend upon the specific components of themixture and the amounts of each present.

According to one aspect of this invention, at least one carboxylic acidacylating agent is reacted under esterification conditions with at leastone polyoxyalkylene demulsifier in amounts such that there is at leastabout 0.001 equivalent of demulsifier for each equivalent of acylatingagent employed. From a consideration of the stoichiometry involved inthe reaction of the carboxylic acid acylating agent and an alcohol,there is theoretically no need to employ more than one mole ofdemulsifier for each equivalent of acylating agent although even greateramounts of demulsifier can be employed, for example, up to two or threemoles per equivalent, particularly if the demulsifier is to function asa diluent or if an excess of a demulsifier is desired to promote anincrease in the rate and quantity of ester produced.

However, it has been found that the desired improvements in lubricantsand fuels provided by the present invention, can be achieved ifsufficient ester of polyoxyalkylene alcohol demulsifier is incorporatedinto the lubricant or fuels so that from about 0.00005% to about 5% byweight of the total weight of the final lubricant or fuel composition isattributable to the polyoxyalkylene alcohol demulsifier moiety of theester. Preferably, the polyoxyalkylene alcohol demulsifier moiety willaccount for about 0.0001% to about 1.0% by weight of the total weight ofthe final lubricant or fuel. Thus, if one completely esterifies theacylating agent with polyoxyalkylene alcohol demulsifier, only a smallamount of such an ester is needed to provide the desired concentrationof the demulsifier moiety in the final lubricant or fuel.

Some of the esters of the polyoxyalkylene alcohol demulsifiers are notinfinitely soluble in lubricating oils and fuels. Due to the smallamounts of ester required as indicated above, solubility is no realproblem. However, if the acylating agent is completely or substantiallycompletely esterified, the resulting ester-containing composition maynot be completely soluble in a lubricating oil or normally liquid fuelat high concentrations. Therefore, incorporating such anester-containing composition into a lubricant or fuel may require mixingthe composition with a large volume of a given lubricant or fuel todissolve or stably disperse it. Due to such solubility considerations,the number of equivalents of demulsifier for each equivalent ofacylating agent desirably will not exceed 0.5 and usually will notexceed 0.25. Preferably, for most uses in lubricants and fuels, thenumber of equivalents of demulsifier for each equivalent of acylatingagent will not exceed about 0.1. The remaining unreacted acylating agentin the ester-containing composition thus produced functions as apeptizing agent and helps solubilize or stably disperse the esterproduct. Moreover, when the unreacted acid groups of the acylating agentare the carboxyl groups per se, the corresponding anhydrides, or loweralkyl esters (e.g., carbomethoxy, carboethoxy, etc.), the acylatingagent also serves as a dispersant or detergent. See, for example, U.S.Pat. No. 3,288,714; 3,346,354; and 3,381,022.

According to a more preferred aspect of this invention, theester-containing composition resulting from the reaction of theacylating agent with the polyoxyalkylene alcohol demulsifier is itselfcontacted with at least one member selected from the class consisting ofpolyhydric alcohols, amines, and basically reacting Group IIa metalcompounds or mixtures thereof under esterification conditions as definedabove. The amount of polyhydric alcohol, amine, metal compound ormixture of two or more of these is such that there is at least about0.01 equivalent thereof for each equivalent of acylating agent initiallyemployed in the reaction with the emulsifier. Where the acylating agenthas been reacted with the demulsifier in amounts such that there is atleast about one equivalent of demulsifier for each equivalent ofacylating agent, this small quantity of polyhydric alcohol, amine, metalcompound, or mixture thereof is sufficient to react with minor amountsof non-esterified carboxyl groups which may be present.

As mentioned above, however, the maximum amount of demulsifier generallyemployed in the reaction with the acylating agent is such that there isnot more than about 0.5, desirably not more than about 0.25, equivalentof demulsifier for each equivalent of acylating agent. It has been foundthat a better product generally results if a combination of demulsifierand the polyhydric alcohol, amine, metal compound or mixture thereof isused which furnishes at least about 0.5 equivalent of the combinationfor each equivalent of acylating agent. For most uses in lubricants andfuels, it is desirable that the ester-containing compositions of thisinvention be substantially free from unreacted carboxyl groups or theirfunctional equivalents. Thus, the combination preferably will provide atleast about one equivalent for each equivalent of acylating agent. Ofcourse, excess polyhydric alcohol, amine, metal compound or mixturethereof can be used. For example, if about 0.1 equivalent of demulsifieris reacted with each equivalent of acylating agent to produce anester-containing composition, then one to ten or more equivalents ofpolyhydric alcohol, amine, metal compound, or mixture thereof may becontacted with the ester-containing composition. However, from theviewpoint of the stoicheometry involved, there is usually no benefit inproviding more than one mole of the polyhydric alcohol, amine, or metalcompound or mixture thereof for each equivalent of acylating agentalthough larger excesses may serve other purposes as mentioned above.Preferably, there will be at least 0.1 equivalent of polyhydric alcohol,amine, metal compound or mixture thereof for each equivalent ofnon-esterified acid group in the ester-containing composition resultingfrom the reaction of the acylating agent and the demulsifier.

In another preferred aspect of the invention, the carboxylic acidacylating agent is reacted simultaneously with both the demulsifier andat least one other reactant of the group selected from the classconsisting of polyhydric alcohols, amines, Group IIa basically reactingmetal compounds, or mixtures of these although the acylating agent canfirst be reacted with said other reactant and that product then reactedwith the demulsifier. According to this aspect of the invention, thereis at least a 0.001 equivalent of demulsifier and at least 0.001equivalent of said other reactant for each equivalent of acylatingagent. As before, the total amount of demulsifier employed generallywill not exceed 0.5, usually 0.25, equivalents per equivalent ofacylating agent. For better results in most lubricant and fuelapplications, there will not be more than about 0.1 equivalent ofdemulsifier for each equivalent of acylating agent. Again, thecombination of demulsifier and said other reactant generally shouldprovide a total of at least 0.5 equivalent for each equivalent ofacylating agent. A preferred minimum amount for said other reactant isthat amount which provides at least about 0.1 equivalent thereof foreach equivalent of acylating agent initially employed.

In a very useful embodiment of this most preferred aspect, apolycarboxylic acid acylating agent having an average of at least aboutfifty aliphatic carbon atoms per molecule exclusive of carboxyl carbonatoms is reacted under esterification conditions with at least onepolyoxyalkylene alcohol demulsifier and at least one polyhydric alkanol,particularly alkanols having at least three alcoholic hydroxyl groupsand up to ten aliphatic carbon atoms, in amounts such that the ratio ofthe equivalents of acylating agent to demulsifier to polyhydric alkanolis represented by the ratio 1:b:c where b ≧ 0.001; c ≧ 0.2, and b + c ≧0.5. Best results appear to be obtained when reactants are broughttogether and reacted simultaneously but it is contemplated that thepolyhydric alkanol can first be reacted with the acylating agent and theproduct of that first reaction then contacted with the demulsifierreactant. It is particularly desirable that the acrylating agent be asubstituted dicarboxylic acid acylating agent in which the substitutentsare derived from 1-olefin polymers and halogenated 1-olefin polymerswhere the substituents have an average molecular weight of about 700 toabout 5000; the polyoxyalkylene alcohol demulsifier should consistessentially of hydrophobic portions comprising ##EQU15## where R' isalkyl of up to three carbon atoms and hydrophylic portions comprising--CH₂ CH₂ O-- groups; the polyhydric alkanol contains at least threealcoholic hydroxyl groups and up to ten carbon atoms; b has a value ofabout 0.004 to about 0.1; and c has a value of about 0.5 to about 6.

Within this more preferred aspect of the invention, the most preferredaspect is the one involving the simultaneous reaction of at least onesubstituted succinic acid or anhydride having constituents derived fromethylenepropylene copolymers, polypropylene, polybutylene, chlorinatedethylenepropylene copolymers, chlorinated propylene, and chlorinatedpolybutylene, under esterification conditions with at least onepolyoxyalkylene polyol having two to three hydroxyl groups andconsisting essentially of hydrophobic portions comprising ##EQU16##groups and hydrophylic portions comprising --CH₂ CH₂ O-- groups, and atleast one polyhydric lower alkanol containing three to six hydroxylgroups and up to six aliphatic carbon atoms where b has a value of 0.005to about 0.05 and c has a value of at least about 0.75.

In another variation of the preferred aspect of this invention, theester-containing composition produced by the reaction of the acylatingagent, the polyoxyalkylene alcohol, and the polyhydric alkanol issubsequently contacted under esterification conditions as defined abovewith a base selected from the group consisting of amines, basicallyreacting Group IIa metal compounds, and mixtures thereof, the amount ofbase being such that there is at least about one equivalent thereof foreach unesterified acid group of the acylating agent, i.e., a carboxylgroup or acylating functional derivative thereof. Preferably, the basewill be an alkylenepolyamine of the type described hereinbefore,preferably an ethylene polyamine having an average of three to sevenamino nitrogens. Again, based on stoichiometric considerations, thereordinarily is no advantage in contacting the ester-containingcomposition with more than about one mole of the base for eachequivalent of unesterified acidic groups in the acylating agent.

As is apparent to those skilled in the art from the foregoingdiscussion, the above descriptions of the various aspects of theprocesses of this invention set forth the total amounts of the variousreactants to be employed in the processes. It is not required that allof the indicated amounts enter into the reaction. In fact, in thosecases where there are obvious stoichiometric excesses, it is impossiblefor all of the reactants to undergo the reaction. As explained above,any unreacted acylating agent actually serves a useful function in theresulting ester-containing compositions and, accordingly, in no wayinterfers with the use of the products as lubricant and fuel additives.Other unreacted materials generally can remain in the product withoutany undue adverse effect on the use of the ester-containing compositionsas lubricant and fuel additives provided they are soluble in thelubricants and fuels. Insoluble reactants can be removed by conventionaltechniques such as distillation, decantation, filtration,centrifugation, and the like. It is also apparent that those skilled inthe art may desire to apply conventional processing techniques to thereactants during or between the various steps of the reactions. Forexample, super atmospheric pressure may be employed in order to expeditethe reaction or to increase the yield. Similarly, sub-atmosphericconditions may be used when stripping out volatile unreacted reactants.It may be desirable to decrease or increase the amount of diluent duringthe various steps in the process. Inert atmospheres may be employed.Likewise, an inert gaseous purge may be employed during the reaction orthereafter to assist in the removal of water from the reaction mixture.Nitrogen gas can be blown through the reaction mass during and/or afterthe reaction if it is desired to use such a purge. It is alsocontemplated that the reactions can be conducted under reflux conditionsand that mechanical agitation will be applied to the reaction mixture inorder to expedite the reaction. However, these and other expedients arewell known in the art and do not require a detailed discussion herein.

The reaction products produced according to the processes contemplatedby this invention as described hereinabove and illustrated hereinafterare complex ester-containing compositions. Thus, the product can containesters and unreacted acylating agent; esters, unreacted acylating agent,and metal salts; ester, metal salt, and acylated amines such as amides,imides; esters and acylated amines; and the like. For that reason, it isnot possible to describe the ester-containing compositions of thepresent invention other than in terms of the process by which they areproduced.

It is not understood how the demulsifier moiety provides the improvementfound in the compositions of this invention. It is theorized that aswater forms in the lubricant or fuel such as by condensation, the waterslowly hydrolyzes the esterified demulsifier so as to releasedemulsifier as the need for it comes in to being. This provides a sortof prolonged, controlled release of demulsifier into the lubricant orfuel and results in improved aqueous emulsion resistance. The manner inwhich the dispersancy properties, the rust properties, and/or thevarnish reduction properties of the products is improved is notunderstood. It is clear, however, that incorporating the emulsifier intothe fuel or lubricant in the form of its ester gives superiorperformance over the simple addition of the demulsifier per se to thelubricant or fuel. Furthermore, more of the demulsifier can be dissolvedor stably dispersed in the lubricant or fuel through the incorporationof an ester of the demulsifier relative to the amounts of the freedemulsifier which can be dissolved or dispersed in the lubricant orfuel.

The following examples further illustrate the processes andester-containing compositions of the present invention. Unless otherwiseindicated, all percentages and parts represent percent by weight andparts by weight, respectively.

EXAMPLE 1

a. A high molecular weight carboxylic acid acylating agent is preparedby heating an equimolar amount of a chlorinated polyisobutylene havingan average molecular weight of 2300 and a chlorine content of about 4.7%with methacrylic acid at about 190°-210°C. for about 15 hours.Subsequently, one equivalent of the acid is reacted with one equivalentof a polyoxyalkylene triol demulsifier having an average molecularweight of about 4800 prepared by first reacting propylene oxided withglycerol and thereafter reacting that product with ethylene oxide toproduce a product where --CH₂ CH₂ O-- groups make up about 18% by weightof the demulsifiers average molecular weight in the prescence of a lowviscosity mineral oil diluent for about ten hours at a temperature ofabout 190°-205°C. and subsequently filtered. The filtrate is the desiredester-containing composition in an oil diluent.

b. Part (a) is repeated using an equivalent ratio of acylating agent totriol of about 1:0.1.

EXAMPLE 2

A high molecular weight monocarboxylic acid acylating agent is preparedaccording to the general procedure of Example 1 (a) by reacting equalmolar amounts of chlorinated polyisobutylene having an average molecularweight of about 1000 with acrylic acid. This acylating agent is thenreacted with the triol of Example 1 (a) and TME simultaneously in thepresence of a low viscosity mineral oil diluent in an equivalent ratioof about 1:0.01:1.5 by heating these reactants at about 200°-210°C. forabout 12 hours. The reaction mass is then filtered, the filtrate beingan oil solution of the desired product.

EXAMPLE 3

a. A mixture of 108 parts of a polyisobutenyl-substituted succinic acidanhydride having an equivalent weight of about 540 (prepared by reactingchlorinated polyisobutylene characterized by an average molecular weightof about 1:050 and a chlorine content of 4.3% with an equal molarquantity of maleic anhydride), 480 parts of the triol of Example 1(a)(e.g., an equivalent ratio of acrylating agent to triol of about 1:1.5)and 380 parts of mineral oil is heated for about 8.3 hours at200°-205°C. while blowing nitrogen gas through the mixture to assist inwater removal. On standing, the reaction product separates into twoliquid layers illustrating the point made above to the effect that someof the ester-containing compositions contemplated by the presentinvention are not instantly soluble in lubricating oils and fuels.However, this ester-containing product can be dissolved or stablydispersed in larger volumes of lubricating oils or fuels as explainedhereinbefore. Nevertheless, it is clearly more convenient to control theratio of reactants so that the ester of polyoxyalkylene alcoholdemulsifier present in the ester-containing composition produced in thereaction is an amount which will remain stably dispersed or dissolved inthe other components of the reaction mass. The presence of ashlessdispersants of the general type disclosed in U.S. Pat. Nos. 3,172,892and 3,219,666 assist in solubilizing or stably dispersing the esters ofthe demulsifiers of this invention. The acylated nitrogen compositionsof those patents prepared by reacting a substituted succinic acid oranhydride, such as an olefin polymer-substituted succinic acid oranhydride, with an alkylene polyamine are especially useful. Suchashless dispersants can be beneficially employed in the preparation ofthe ester-containing compositions of this invention in amountscomprising from about 0.1% to about 20% by weight of the total reactionmass to promote solubility of dispersion of those compositionscharacterized by solubility problems. Obviously, the ashless dispersantwhen employed for this purpose can remain in the product to continuethis function and to perform its usual function in the lubricant orfuel.

b. The general procedure of (a) was repeated except that the acylatingagent was simultaneously reacted with the triol and TMP in an equivalentratio of about 1:0.03:2.

EXAMPLE 4

Following the general procedure of Example 3(a), the acylating agent ofthat example is reacted with a polyoxyalkylene diol demulsifier havingan average molecular weight of about 3800 and consisting essentially ofa hydrophobic base of ##EQU17## units with hydrophylic terminal portionsof --CH₂ CH₂ O-- units, the latter comprising approximately 10% byweight of the demulsifier, in an equivalent ratio of about 1:0.01.

EXAMPLE 5

A mixture consisting of 1869 parts (3.5 equivalents) of apolyisobutenyl-substituted succinic acid anhydride as described inExample 3(a), 236 parts (6.95 equivalents) of pentaerythritol, 59 parts(0.04 equivalent) of the triol of Example 1(a) and 700 parts of lowviscosity diluent oil are heated at 190°-200°C. for 11 hours duringwhich time nitrogen gas is bubbled through the mixture. Subsequently,700 parts of oil is added and the resulting mass filtered. The filtrateis a 40% oil solution of the desired ester-containing composition.

EXAMPLE 6

A reaction mixture consisting of 1780 parts (1.65 equivalents) of theacylating agent of Example 3(a), 220 parts of pentaerythritol (6.47equivalents) 220 parts (0.14 equivalent) of the triol of Example 1(a)and 770 parts of low viscosity diluent oil is heated for 11 hours at190°-200°C. with nitrogen blowing. Thereafter, 760 parts of diluent oilis added and the resulting mass filtered. The filtrate is a 40% oilsolution of the desired ester-containing composition.

EXAMPLE 7

A mixture of 1869 parts of a polyisobutenyl-substituted succinicanhydride as described in Example 3(a) and 67 parts of diluent oil areheated to 90°C. while blowing nitrogen gas through the mass. Then amixture of 132 parts of a polyethylenepolyamine mixture having anaverage composition corresponding to that of tetraethylene pentamine andcharacterized by a nitrogen content of about 36.9% and an equivalentweight of about 38 and 33 parts of a triol as described in Example 1(a)is added to the preheated oil and acylating agent over a period of about0.5 hours. An exothermic reaction takes place causing the temperature torise to about 120°C. Thereafter the mixture is heated to 170°C. andmaintained at that temperature for about 4.5 hours. Additional oil (666parts) is added and the product filtered. The filtrate is an oilsolution of a desired ester-containing composition.

EXAMPLE 8

A mixture of 1000 parts of a polyisobutylene having a molecular weightof about 1000 and 98 parts of maleic anhydride are heated at atemperature of about 200° to 210°C. in an inert atmosphere for a periodof about 24 hours. The reaction mixture is then cooled to about 65°C.and approximately 500 parts of hexane are added and the mass filtered.Then the hexane removed from the filtrate by stripping to a temperatureof 175°C. at a pressure of 10 millimeters (Hg).

The polyisobutenyl-substituted succinic anhydride thus prepared is thenreacted with a polyethylenepolyamine mixture as described in Example 7while maintaining a temperature of about 200°-210°C. in an equivalentratio of about 1:0.7. Thereafter, a sufficient amount of thepolyoxyalkylene diol described in Example 4 is added to the reactionmass to provide one equivalent of diol for each equivalent of unreactedacid group remaining in the polyisobutenyl-substituted succinicanhydride and the mixture is again heated at a temperature of about200°-210°C. for approximately 10 hours. Diluent oil is added and theresulting mass filtered, the filtrate being an oil-solution of thedesired ester-containing composition.

EXAMPLE 9

a. A mixture comprising 1885 parts (3.64 equivalents) of the acylatingagent described in Example 3(a), 248 parts (7.28 equivalents) ofpentaerythritol, and 64 parts (0.03 equivalent) of the polyoxyalkylenediol described in Example 4 are heated from room temperature to 200°C.over a 1 hour period while blowing the mass with nitrogen gas. The massis then maintained at a temperature of about 200°-210°C. for anadditional period of about 8 hours while continuing the nitrogenblowing.

b. To the ester-containing composition produced according to (a) above,there is added over a 0.3 hour period (while maintaining a temperatureof 200°-210°C. and nitrogen blowing) 39 parts (0.95 equivalent) of apolyethylenepolyamine mixture having an equivalent weight of about 41.2.The resulting mass is then maintained at a temperature of about206°-210°C. for 2 hours during which time the nitrogen blowing iscontinued. Subsequently, 1800 parts of low viscosity mineral oil isadded as a diluent and the resulting mass filtered at a temperature ofabout 110°-130°C. The filtrate is a 45% oil solution of the desiredester-containing composition.

Example 10

a. Another ester-containing composition of the type contemplated by thepresent invention is prepared by heating a mixture of 3215 parts (6.2equivalents) of a polyisobutenyl-substituted succinic anhydride asdescribed in Example 3(a), 422 parts (12.4 equivalents) ofpentaerythritol, 55 parts (0.029 equivalent) of the polyoxyalkylene dioldescribed in Example 4, and 55 parts (.034 equivalent) of the triol ofExample 1(a) to a temperature of about 200°-210°C. with nitrogen blowingfor about 6 hours. The resulting reaction mixture is an estercontainingcomposition of the type contemplated by the present invention.

b. Subsequently, 67 parts (1.63 equivalents) of a polyethylenepolyaminemixture having an equivalent weight of about 41.2 is added to thecomposition produced according to (a) over a 0.6 hour period whilemaintaining a temperature of about 200°-210°C. with nitrogen blowing.The resulting mass is then heated an additional 2 hours at a temperatureof about 207°-215°C. with continued nitrogen blowing and subsequently2950 parts of low viscosity mineral diluent oil are added to thereaction mass. Upon filtration, there is produced a 45% oil solution ofan ester-containing composition of the type contemplated by the presentinvention.

EXAMPLE 11

a. A mixture comprising 3204 parts (6.18 equivalents) of the acylatingagent of Example 3(a) above, 422 parts (12.41 equivalents) ofpentaerythritol, 109 parts (0.068 equivalent) of the triol of Example1(a) is heated to 200°C. over a 1.5 hour period with nitrogen blowingand thereafter maintained between 200°-212°C. for 2.75 hours withcontinued nitrogen blowing.

b. Subsequently, there is added to the ester-containing compositionproduced according to (a) above, 67 parts (1.61 equivalents) of apolyethylenepolyamine mixture having an equivalent weight of about 41.2.This mass is then maintained at a temperature of about 210°-215°C. forabout one hour. Then 3070 parts of low viscosity mineral diluent oil isadded to the mass and this material is filtered at a temperature ofabout 120°C. The filtrate is a 45% oil solution of an ester-containingcomposition of the type contemplated by the present invention.

EXAMPLE 12

Sufficient barium hydroxide is added to the ester-containing compositionproduced according to Example 1(b) to provide one equivalent of bariumfor each equivalent of acylating agent employed in the preparation ofthe ester-containing composition. The mixture is heated with stirringfor about 1 hour while maintaining a temperature of about 150°-160°C.The reaction mass is then filtered, the filtrate being an oil solutionof another ester-containing composition of the type contemplated by thepresent invention.

When the process of Example 12 is repeated using equivalent quantitiesof calcium ethoxide or strontium isopropoxide or magnesium oxide in theplace of the barium hydroxide, an oil solution of the correspondingester-containing composition of the type contemplated by the presentinvention will be obtained.

EXAMPLE 13

Following the general procedure of Example 5, an acylating agent of thetype described in Example 3(a) is simultaneously reacted withpentaerythritol, the polyoxyalkylene diol described in Example 4, andcalcium hydroxide in a ratio of equivalents of 1:0.5:0.02:0.4. Uponfiltration, there is produced a filtrate which is an oil solution of thedesired ester-containing composition.

When the process of Example 13 is repeated using equivalent quantitiesof barium methoxide or strontium hydroxide or magnesium oxide in theplace of the calcium hydroxide, an oil solution of the desiredester-containing composition will be obtained.

EXAMPLE 14

a. Following the general procedure of Example 9(a), an acylating agentas described in Example 3(a), the polyoxyalkylene diol described inExample 4, and sorbitol are simultaneously reacted in equivalent ratioof 1:0.015:3.

b. Following the general procedure of Example 9(b), the ester-containingcomposition produced in (a) is contacted with 1-aminoethyl piperazine inamounts such that there is one equivalent of amine for each equivalentof acylating agent employed in the initial preparation of theester-containing composition.

EXAMPLE 15

a. Polyisobutylene having an average molecular weight of 2500 is reactedwith maleic anhydride in a molar ratio of about 1:2 in the presence ofchlorine gas according to the procedure described in U.S. Pat. No.3,215,707 or 3,231,587 to produce a polyisobutylene material containingan average of two succinic acid anhydride groups per molecule.

This acylating agent is then reacted with the polyoxyalkylene triol ofExample 1(a) and mannitol according to the general procedure set forthin Example 11(a) in an equivalent ratio of about 1:0.05:1.5 to producean ester-containing composition of the type contemplated by thisinvention.

EXAMPLE 16

A tricarboxylic acid is prepared by reacting brominated poly(1-hexene)having an average molecular weight of about 2000 and a bromine contentof 4% by weight with 2-pentene-1,3,5-tricarboxylic acid at about 150°C.for 20 hours. Then following the general procedure of Example 10(a),three equivalents of this acid is simultaneously reacted with oneequivalent of propylene glycol, 1.5 equivalents oftris-(β-hydroxyethyl)amine, and 0.075 equivalent of a polyoxyalkylenealcohol prepared under conventional oxyalkylation procedures through thereaction of dinonylphenol with propylene oxide and subsequently withethylene oxide to produce a monoalkylphenyl ether of a polyoxyalkylenealcohol having an average molecular weight of about 5000 where --CH₂ CH₂O-- groups comprise about 12%-15% of their average molecular weight.

EXAMPLE 17

Following the general procedure of Example 11(a) and (b), anotherester-containing composition is prepared by replacing thepolyoxyalkylene triol demulsifier employed there with an equivalentamount of another polyoxyalkylene triol demulsifier having an averagemolecular weight of about 2000 prepared by reacting under routineoxyalkylation conditions, glycerol with propylene oxide to form ahydrophobic base and then reacting this base with ethylene oxide inamounts such that --CH₂ CH₂ O-- units comprise about 9%-12% by weight ofthe average molecular weight.

EXAMPLE 18

a. A polyoxyalkylene tetrol demulsifier is prepared by reacting underroutine oxyalkylation conditionsN,N,N',N'-tetrakis(β-hydroxypropyl)ethylenediamine with propylene oxideand then with ethylene oxide to produce a material havving an averagemolecular weight of about 5400, about 11% of which is attributable to--CH₂ CH₂ O-- units.

As used in the present specification and claims, the language routine orconventional oxyalkylation procedures refers to the general proceduresused by those skilled in the art to react alkylene oxides with materialshaving reactive hydrogens such as phenols, alcohols, amines, etc. Theseconditions usually involve contacting the alkylene oxide with the otherreactive material, usually in the presence of an inert diluent, such asthose described hereinbefore, in the desired mole ratio at a temperatureof about 50°-200°C., usually about 100°-150°C. Superatmosphericpressure, e.g., ten to thirty p.s.i. are advantageously employed.Oxyalkylation are well known and need no detailed discussion here; see,for example, U.S. Pat. Nos. 3,251,664, 2,792,369, and 2,792,371 andpatents cited therein for a detailed discussion of such procedures.

b. The acylating agent as described in Example 15(a) is simultaneouslyreacted with the tetrol of (a), pentaerythritol, and TMP in anequivalent ratio of 1:0.004:0.5:0.5 following the general procedure ofExample 10(a).

EXAMPLE 19

a. Three thousand parts (5.5 equivalents) of apolyisobutenyl-substituted succinic acid anhydride as described inExample 3(a), 330 parts (8 equivalents) of a polyethylene polyaminemixture having an equivalent weight of about 41.2 and 93 parts of thepolyoxyalkylene polyol of Example 4 are reacted by adding the anhydrideto a mixture of the amine and polyol preheated to about 130°C. andthereafter heating the resulting mixture to about 210°C. for about 4hours while blowing with nitrogen. Then 2121 parts of mineral diluentoil are added and the mass is filtered at a temperature of about 150°C.The filtrate is an oil solution of the desired product.

b. The general procedure of (a) is followed using 3000 parts of theanhydride, 163 parts (4 equivalents) of the amine, and 93 parts of thepolyoxyalkylene polyol. After addition of 2010 parts of mineral diluentoil, the reaction mixture is filtered. The filtrate is a 45% oilsolution of the desired product.

EXAMPLE 20

a. A mixture comprising 1000 parts of the polyisobutenyl-substitutedsuccinic acid anhydride of Example 3(a), 121 parts of pentaerythritol,31 parts of the polyoxyalkylene polyol of Example 4, and 10 partsimidazole (catalyst) is heated at about 200°-220°C. with nitrogenblowing for about 5.5 hours. Then 937 parts of mineral diluent oil isadded while maintaining nitrogen blowing. The resulting mixture isfiltered at 110°-120°C., the filtrate being a 45% oil solution of thedesired ester-containing composition.

b. Following the general procedure of (a) the same reactants (samequantities also) are heated at 200°-215°C. for ten hours using one partimidazole catalyst.

EXAMPLE 21

a. The general procedure of Example 11(a) was repeated substituting aTETRONIC polyol having an average molecular weight of about 7900 for thepolyoxyalkylene diol of that example in amounts such that the equivalentratio of acylating agent: pentaerythritol: TETRONIC 1501 is about1:2:0.009. The resulting reaction mixture is then treated with thealkylene polyamine mixture of 11(b) following the general procedure ofthat example using sufficient polyamine to provide an equivalent ratioof acylating agent to polyamine of about 1:0.26 based on the totalamount of acylating agent employed. A 45% oil solution of the desiredproduct characterized by a nitrogen content of 0.33%.

b. The general procedure of Example 21(a) is repeated but the amount oftetronic polyol is increased to an amount sufficient to provide 0.018equivalents. The final filtrate is a 45% oil solution of the desiredproduct characterized by a nitrogen content of about 0.32%.

Other ester-containing compositions of the type contemplated by thisinvention are readily prepared by substituting other acylating agents,polyoxyalkylene alcohol demulsifiers, polyhydric alcohols, amines, andbasically reacting Group IIa metal compounds as described above for allor a portion of the corresponding reactants utilized in the foregoingillustrative examples.

The ester-containing compositions of this invention normally will beemployed in mineral lubricating oil base lubricant compositions.However, other lubricating oils, natural and synthetic, of lubricatingviscosity can be used as the base oil. The ester-containing compositionsshould be employed in amounts such that the polyoxyalkylene alcoholmoiety of the esters will constitute at least the percentage of thefinished lubricant composition specified above. Clearly, the amountnecessary to provide the indicated amount of demulsifier additive willdepend on the specific ester-containing composition employed, the otheradditives, if any, present, etc. Generally the ester-containingcompositions will be employed in amounts constituting about 0.1% toabout 20% or more by weight of the finished lubricant, more often, about1%-10% by weight.

Natural oils include animal oils and vegetable oils (e.g., castor oil,lard oil) as well as solvent-refined or acid-refined mineral lubricatingoils of the paraffinic, naphthenic, or mixed paraffinic-naphthenictypes. Oils of lubricating viscosity derived from coal or shale are alsouseful base oils. Synthetic lubricating oils include hydrocarbon oilsand halo-substituted hydrocarbon oils such as polymerized andinterpolymerized olefins (e.g., polybutylenes, propylene-isobutylenecopolymers, chlorinated polybutylenes, etc.); alkyl benzenes (e.g.,dodecylbenzenes, tetradecylbenzene, dinonylbenzenes,di-(2-ethylhexyl)benzenes, etc.); polyphenyls(e.g., bi-phenyls,terphenyls, etc.); and the like. Alkylene oxide polymers andinterpolymers and derivatives thereof where the terminal hydroxyl groupshave been modified by esterification, etherification, etc., constituteanother class of known synthetic lubricating oils. These are exemplifiedby the oils prepared through polymerization of ethylene oxide orpropylene oxide, the alkyl and aryl ethers of these polyoxyalkylenepolymers (e.g., methylpolyisopropylene glycol ether having an averagemolecular weight of 1000, diphenyl ether of polyethylene glycol having amolecular weight of 500-1000, diethyl ether of polypropylene glycolhaving a molecular weight of 1000-1500, etc.) or mono- andpolycarboxylic esters thereof, for example, the acetic acid esters,mixed C₃ -C₈ fatty acid esters, or the C₁₃ Oxo acid diester oftetraethylene glycol. Another suitable class of synthetic lubricatingoils comprises the esters of dicarboxylic acids (e.g., phthalic acid,succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid,fumaric acid, adipic acid, linoleic acid dimer, etc.) with a variety ofalcohols (e.g., butyl alcohol, hexyl alcohol, dodecyl alcohol,2-ethylhexyl alcohol, pentaerythritol, etc.). Specific examples of theseesters include dibutyl adipate, di(2-ethylhexyl)-sebacate, di-n-hexylfumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate,dioctyl phthalate, didecyl phthalate, dieicosyl sebacate, the2-ethylhexyl diester of linoleic acid dimer, the complex ester formed byreacting one mole of sebacic acid with two moles of tetraethylene glycoland two moles of 2-ethyl-hexanoic acid, and the like. Silicon-based oilssuch as the polyalkyl-, polyaryl-, polyalkoxy-, or poly-aryloxysiloxaneoils and silicate oils comprise another useful class of syntheticlubricants (e.g., tetraethylsilicate, tetraisopropyl-silicate,tetra-(2-ethylhexyl)-silicate, tetra-(4-methyl-2-tetraethyl)-silicate,tetra-(P-tert-butylphenyl)-silicate,hexyl-(4-methyl-2-pentoxy)-disiloxane, poly(methyl)-siloxanes,poly(methylphenyl)-siloxanes, etc.). Other synthetic lubricating oilsinclude liquid esters of phosphorus-containing acids (e.g., tricresylphosphate, trioctyl phosphate, diethyl ester of decane phosphonic acid,etc.), polymeric tetrahydrofurans, and the like.

As mentioned supra, the present invention contemplates the presence ofother additives in the lubricating compositions in addition to theester-containing compositions described above. Such additives include,for example, ashless dispersants, detergents of the ash-containing type,viscosity index improving agents, pour point depressants, anti-foamagents, extreme pressure agents, rust inhibitors, oxidation andcorrosion inhibitors, and the like. These other additives can beemployed in the amounts they are normally employed in lubricantcompositions.

The ash-containing detergents are exemplified by oil-soluble neutral andbasic salts of alkali or alkaline earth metals with sulfonic acids,carboxylic acids or organic phosphorous acids characterized by at leastone direct carbon-to-phosphorous linkage such as those prepared by thetreatment of an olefin polymer (e.g., polyisobutene having a molecularweight of 1000) with a phosphorizing agent such as phosphoroustrichloride, phosphorous heptasulfide, phosphorous pentasulfide,phosphorous trichloride and sulfur, white phosphorous and a sulfurhalide, or phosphorothioate chloride, The most commonly used salts ofsuch acids are those of sodium, potassium, lithium, calcium, magnesium,strontium and barium.

The term "basic salt" is used to designate the metal salts wherein themetal is present in stoichiometrically larger amounts than the organicacid radicals. The commonly employed methods for preparing the basicsalts involves heating a mineral oil solution of an acid with astoichiometric excess of a metal neutralizing agent such as a metaloxide, hydroxide, carbonate, bicarbonate, or sulfide at a temperatureabove about 50°C. and filtering the resulting mass. The use of a"promoter" in the neutralization step to aid in the incorporation of alarge excess of metal likewise is known. Examples of compounds useful asthe promoter include phenolic substances such as phenol, naphthol,alkylphenols, thiophenols, sulfurized alkylphenols, condensationproducts or formaldehyde with such phenolic substances, alcohols such asmethanol, 2-propanol, octyl alcohol, Cellosolve, Carbitol, ethyleneglycol, cyclohexyl alcohol; amines such as aniline, phenylene diamine,phenothiazine, phenyl-beta-naphthylamine, and dodecylamine. Aparticularly effective method for preparing the basic salts comprisesmixing an acid with an excess of a basic alkaline earth metalneutralizing agent, a phenolic promoter compound, and a small amount ofwater, and carbonating the mixture at an elevated temperature such as60° to 200°C.

Extreme pressure agents and corrosion-inhibiting andoxidation-inhibiting agents are exemplified by chlorinated aliphatichydrocarbons such as chlorinated wax; organic sulfides and polysulfidessuch as benzyldisulfide, bis-(chlorobenzyl)-disulfide, dibutyltetrasulfide, sulfurized sperm oil, sulfurized methyl ester of oleicacid, sulfurized alkylphenol, sulfurized dipentene, and sulfurizedterpene; phosphosulfurized hydrocarbons such as the reaction product ofphosphorus sulfide with turpentine or methyloleate; phosphorous estersincluding principally dihydrocarbon and tri-hydrocarbon phosphites suchas dibutylphosphite, diheptyl phosphite, dicyclohexyl phosphite,pentylphenyl phosphite, dipentyl phenyl phosphite, tridecyl phosphite,distearyl phosphite, dimethyl naphthyl phosphite, oleyl 4-pentyl phenylphosphite, polypropylene -(molecular weight 500)-substituted phenylphosphite, diisobutyl-substituted phenyl phosphite; metal thiocarbamatessuch as zinc dioctyldithiocarbamate and barium heptylphenyldithiocarbamate; Group II metal phosphorodithioates such as zincdicyclohexyl phosphorodithioate, zinc dioctyl phosphorodithioate, bariumdi(heptylphenyl)-phosphorodithioate, cadmium dinonyl phosphorodithioate,and a zinc salt of a phosphorodithioic acid produced by the reaction ofphosphorus pentasulfide with an equal molar mixture of isopropyl alcoholand n-hexyl alcohol.

When employed as fuel additives, the base fuel will generally be anormally liquid petroleum distillate fuel such as diesel fuel, aviationfuel, gasoline, kerosene, fuel oil and the like. Usually, thedispersancy, aqueous emulsion, and rust problems in fuels is not asgreat as in lubricant compositions. Thus, while those amounts ofester-containing compositions which will furnish the previouslyindicated concentrations of demulsifier moiety in the final fuelcomposition are useful, there usually will not be any need to exceedthat amount of ester-containing composition necessary to provide about0.1%, more often, 0.05% by weight demulsifier moiety in the final fuel.Again, the amount of ester-containing composition employed in aspecified fuel will depend on the particular fuel and the amounts andkinds of other additives present in the fuel.

Other conventional fuel additives such as smoke suppressants (forexample, the ash-containing detergents described above, particularlyoverbased barium detergents) ashless dispersants, anti-icing agents,anti-stalling agents, lead scavengers, lead alkyl antiknock additives,dyes, corrosion inhibitors, lead octane appreciators, etc., such astetraethyl lead, tetramethyl lead, dimethyldiethyl lead, tetravinyllead, t-butyl acetate, tri-(β-chloroethyl)-phosphate, isopropanol, andthe like.

The following are illustrative of the lubricants and fuel compositionsof this invention.

Composition A

SAE 10W-40 mineral lubricating oil containing 0.5% of the filtrate ofExample 1(b).

Composition B

SAE 50 mineral lubricating oil containing 3.5% of the filtrate ofExample 3(b), 1.5% of an acylated nitrogen composition prepared byreacting in about a 1:1 equivalent ratio at about 150°C.polyisobutenyl(M.W. -1100)-substituted succinic anhydride with acommercial polyethylene polyamine mixture having an average compositioncorresponding to that of tetraethylene pentamine, and 0.06% ofphosphorus as the zinc salt of di-n-octyl-phosphorodithioate.

Composition C

SAE 10W-30 mineral lubricating oil containing 5% of the filtrate ofExample 9(b), 0.075% of phosphorus as the zinc salt of a mixture ofequimolar amounts of diisopropyl phosphorodithioic acid anddi-n-decylphosphorodithioic acid, and 2.0% sulfate ash as a basic bariumdetergent prepared by carbonating at 150°C. a mixture comprising mineraloil, one mole of barium didecylbenzene sulfonate, and 1.5 moles ofbarium hydroxide in the presence of 0.7 mole of octylphenol as thepromoter.

Composition D

SAE 10 mineral lubricating oil containing 6.5% of the filtrate ofExample 11(b), 0.06% phosphorus as the adduct of one mole of zincdicyclohexylphosphorodithioate and 0.3 mole of ethylene oxide, 2% ofsulfurized sperm oil having a sulfur content of 10%, 3% of apoly-(alkylmethacrylate) viscosity index improver, and 0.003% of apoly(alkylsiloxane) antifoam agent.

Composition E

SAE 20 mineral lubricating oil containing 0.5% of the composition of17(b), 2.5% of the filtrate of Example 15(a), 0.08% of phosphorus as thezinc salt of a phosphorodithioic acid prepared by the reaction ofphosphorus pentasulfide with an equimolar mixture of n-butyl alcohol anddodecyl alcohol, 2.5% of a basic barium detergent prepared bycarbonating a mineral oil solution containing one mole of sperm oil, 0.6mole of octylphenol, two moles of barium oxide, and a small amount ofwater at 150°C.

Composition F

A synthetic lubricating oil consisting essentially of the diethyletherof polypropylene glycol having an average molecular weight of about 1500containing 0.75% of the filtrate of Example 15(a).

Composition G

Gasoline containing 0.001% of the filtrate of Example 7.

COmposition H

Diesel fuel containing 0.025% of the filtrate of Example 12.

Composition I

Kerosene-containing 0.07% of the filtrate of Example 11(b).

Composition J

Gasoline containing 0.001% of the filtrate of Example 9(b).

The improvement in rust resistance demonstrated by the ester-containingcompositions of this invention is illustrated by the results obtained inthe Puia Falcon engine test as shown in Table I. A rating of 10indicates no rust.

                  TABLE I                                                         ______________________________________                                        Rust Ratings                                                                  Compo- Overall     Average     Average                                        sition Engine Rust Lifter Rust Crankshaft Rust                                ______________________________________                                        AA     6.8         6.5         6.9                                            BB     9.7         9.8         9.8                                            CC     9.5         9.5         9.5                                            DD     9.4         9.5         9.5                                            ______________________________________                                    

Compositions AA and BB are the same except for the evaluated additive.AA contains about 3.14% of a filtrate containing about 45% mineraldiluent oil and produced according to the general procedure of Example11(a) except the polyoxyalkylene polyol demulsifier reactant is omitted.BB contains about 3.4% of a filtrate containing about 45% diluentmineral oil produced according to the general procedure of Example 11(a)and (b) by reacting 1750 parts of the acylating agent with 211.5 partsof pentaerythritol and 54.5 parts of the polyoxyalkylene polyol andcontacting that reaction mixture with 34 parts of the ethylene polyaminemixture. The lubricating compositions of CC and DD are the same exceptthat the former contains about 4.5% of the filtrate produced accordingto Example 11(b) and the latter contains the same amount of the filtrateof Example 9(b).

The excellent emulsion sludge-resisting characteristics of theester-containing compositions of this invention is shown by the Falconengine test results presented in Table II. This test utilizes a FordFalcon six cylinder engine operating on a cycling procedure consistingof 45 minutes at idle 500 RPM, no load, followed by 120 minutes at 2500RPM, 31 BHP. The engine is modified by providing for water cooling ofthe rocker arm cover in order to maintain a cover temperature of about105°-115°F. During the cycle, the blow-by is passed through a condenserand the condensate is returned to the crankcase. The cycle is repeatedfive times in succession each day (for 13 3/4 hours of engineoperation), and then the engine is shut down for the remainder of theday (for 10 1/4 hours). This completes a day's running.

The test is run on a consecutive day-to-day basis. Daily test evaluationconsists of rating the rocker arm cover for emulsion deposits on anumerical scale of 1 to 10 where 10 represents maximum cleanliness,i.e., freedom from aqueous emulsion deposits. The rocker arm cover isremoved and inspected after each 13 3/4 hours of operation and the coverthen immediately replaced.

                                      TABLE II                                    __________________________________________________________________________           Emulsion Ratings                                                              Rating on Indicated Test Day                                           Composition                                                                          1st 2nd 3rd 4th 5th 6th 7th                                                                              8th                                         __________________________________________________________________________    EE     4.5 3.5 --  --  --  --  -- --                                          FF     7.5 7   7.5 7   6.5 4.5 -- --                                          GG     7.5 7.5 8   7.5 7   6.5 5  4                                           __________________________________________________________________________

Each of the lubricating compositions was the same except for thedispersant and each contained 4.35% of a 45% oil solution of theevaluated dispersant. Composition EE contained the same dispersant asComposition AA while Composition FF and GG contained a 45% oil solutionof the ester-containing compositions of Examples 9(b) and 11(b),respectively.

The improvement in dispersancy characteristics is shown by the varnishratings achieved in the Ford Sequence VB test results present in TableIII. The lubricating compositions each contained 4% of a 45% oilsolution of the evaluated dispersant but were otherwise the same.

                  TABLE III                                                       ______________________________________                                                   Varnish Ratings                                                    Composition  Overall Engine   Piston                                                       Varnish*         Varnish**                                       ______________________________________                                        HH           34.6             6.7                                             II           41.8             9.1                                             JJ           45.1             8.7                                             ______________________________________                                          *Rating Scale of 0 to 50, 50 being best rating                                **Rating Scale of 0 to 10, 10 being best rating                         

The dispersant of HH is the same as that described for Composition AAand the dispersants employed in II and JJ are the ester-containingfiltrates of Example 9(b) and 11(b) respectively.

From the foregoing, it is clear that the ester-containing compositionsof this invention are all useful as dispersants in lubricants and fuelsand that in addition to their dispersancy capabilities, they arecharacterized by improved emulsion and rust properties.

Of course, the description of the invention as presented hereinbefore isconcerned with the preparation of dispersants which will performsatisfactorily under conditions where emulsion sludge would otherwise bea problem. Thus, if the dispersants described herein are to be employedin an environment where emulsion sludge is not a problem, excellentdispersants can be prepared for that environment simply by eliminatingthe reaction of the high molecular weight carboxylic acid acylatingagent with the polyoxyalkylene alcohol demulsifiers. For example, in theabove illustrative examples, e.g., Examples 2, 5, 7, 8, 9, 10, 11, 12,13, 14, 15, 19, and 21, elimination of the polyoxyalkylene alcoholdemulsifier reactants produces dispersants having excellentsludge-dispersing capabilities.

What is claimed is:
 1. Oil-soluble carboxylic acid esters prepared by aprocess comprising the reaction ofA. at least one substantiallysaturated aliphatic hydrocarbon polycarboxylic acid acylating agenthaving an average of at least thirty aliphatic carbon atoms per moleculeexclusive of the carboxylic carbon atom and being substantially freefrom oil-solubilizing pendant groups; with B. at least onepolyoxyalkylene alcohol which is a demulsifier for aqueous emulsion, hasan average molecule weight in the range of from about 1,000 to about10,000, and is a block polymer comprising (1) a hydrophobic portioncorresponding to the formula, --CH(R')-CH₂ -O--, wherein R' is an alkylgroup of up to three carbon atoms, and (2) from about 5% to about 40% byweight of a hydrophilic portion corresponding to the formula, --CH₂ -CH₂-O--; and C. at least one primary or secondary amine; wherein the totalamount of (A), (B) and (C) used in the reaction is such that there is atleast 0.001 equivalent of (B), and at least 0.01 equivalent of (C) perequivalent of (A).
 2. The ester of claim 1, wherein the polyoxyalkylenealcohol has an average molecular weight in the range of from about 2,000to about 7,000 has from two to four hydroxy groups and the hydrophiliccontent is from about 10% to about 30% by weight.
 3. The esters of claim1, wherein the total amount of (B) and (C) is such that there is atleast about 0.5 equivalent of the combination of (B) and (C) for eachequivalent of (A).
 4. The esters of claim 3, wherein the amine component(C) is an alkylene polyamine having two to three carbon atoms in thealkylene groups and three to seven amino nitrogens.
 5. The esters ofclaim 4, wherein the carboxylic acylating agent was prepared by thereaction of maleic acid or anhydride with an ethylenically unsaturatedhydrocarbon or halogenated hydrocarbon having an average of at leastfifty carbon atoms.
 6. The esters of claim 5, wherein the ethylenicallyunsaturated hydrocarbon or halogenated hydrocarbon is a 1-olefin polymeror a chlorinated 1-olefin polymer.
 7. The esters of claim 6, wherein the1-olefin polymer or chlorinated 1-olefin polymer is a polybutylene orchlorinated polybutylene.
 8. The esters of claim 1, wherein theacylating agent is a substantially saturated aliphatic hydrocarbonsubstituted succinic acid or anhydride, wherein the substituents arederived from the group consisting of ethylene-propylene copolymer,polypropylene, polybutylene, chlorinated ethylene-propylene copolymer,chlorinated polypropylene and chlorinated polybutylene.
 9. The esters ofclaim 1, wherein (A) is reacted with (B) and (C) simultaneously.
 10. Theesters of claim 1, wherein the ratio of equivalents of (A) to (B) and(C) is represented by the ratio of l:b:c, where b ≧ 0.001, c ≧ 0.2, andb+c ≧ 0.5.
 11. Oil soluble carboxylic acid esters prepared by a processcomprising the reaction ofA. at least one substantially saturatedaliphatic hydrocarbon substituted succinic acid or anhydride wherein thesubstitutents are derived from a 1-olefin polymer or a halogenated1-olefin polymer, and have an average molecular weight in the range offrom about 700 to about 5,000; with B. at least one polyoxyalkylenealcohol which is a demulsifier for aqueous emulsions, has an averagemolecular weight in the range of from about 1,000 to about 10,000, andis a block polymer comprising (1) a hydrophobic portion corresponding tothe formula, --CH(R')-CH₂ -O--, wherein R' is an alkyl group of up totwo carbon atoms and (2) from about 5% to about 40% by weight of ahydrophilic portion corresponding to the formula, -CH₂ -CH₂ -O--; and C.at least one alkylene polyamine having two to three carbon atoms in thealkylene groups and three to seven amino nitrogens; wherein the totalamount of (A), (B) and (C) used in the reaction is such that there is atleast 0.001 equivalent of (B), and at least 0.01 equivalent of (C) perequivalent of (A).
 12. The esters of claim 11, wherein the alkylenepolyamine is polyethylene polyamine.
 13. The esters of claim 11, whereinthe polyoxyalkylene alcohol has an average molecular weight in the rangeof from about 2,000 to about 7,000, has from two to four hydroxy groups,and the hydrophilic content is in the range of from about 10% to about30% by weight.
 14. The esters of claim 11, wherein the 1-olefin polymeror chlorinated 1-olefin polymer is a polybutylene or chlorinatedpolybutylene.
 15. The esters of claim 11, wherein (A) is reacted with(B) and (C) simultaneously.